FR567927A - Development of central battery microphones - Google Patents

Development of central battery microphones

Info

Publication number
FR567927A
FR567927A FR567927DA FR567927A FR 567927 A FR567927 A FR 567927A FR 567927D A FR567927D A FR 567927DA FR 567927 A FR567927 A FR 567927A
Authority
FR
France
Prior art keywords
microphones
development
central battery
battery
central
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
Other languages
French (fr)
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Compagnie Francaise Thomson Houston SA
Original Assignee
Compagnie Francaise Thomson Houston SA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Compagnie Francaise Thomson Houston SA filed Critical Compagnie Francaise Thomson Houston SA
Application granted granted Critical
Publication of FR567927A publication Critical patent/FR567927A/en
Expired legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
    • H04R21/00—Variable-resistance transducers
    • H04R21/02—Microphones
    • H04R21/021—Microphones with granular resistance material

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Acoustics & Sound (AREA)
  • Signal Processing (AREA)
  • Electrostatic, Electromagnetic, Magneto- Strictive, And Variable-Resistance Transducers (AREA)
FR567927D 1922-08-30 1922-08-30 Development of central battery microphones Expired FR567927A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
FR567927T 1922-08-30

Publications (1)

Publication Number Publication Date
FR567927A true FR567927A (en) 1924-03-12

Family

ID=8948131

Family Applications (1)

Application Number Title Priority Date Filing Date
FR567927D Expired FR567927A (en) 1922-08-30 1922-08-30 Development of central battery microphones

Country Status (2)

Country Link
FR (1) FR567927A (en)
GB (1) GB203333A (en)

Also Published As

Publication number Publication date
GB203333A (en) 1925-01-29

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